45687 Commits

Author SHA1 Message Date
Vivek Goyal
39a25b2b37 ovl: define ->get_acl() for overlay inodes
Now we are planning to do DAC permission checks on overlay inode
itself. And to make it work, we will need to make sure we can get acls from
underlying inode. So define ->get_acl() for overlay inodes and this in turn
calls into underlying filesystem to get acls, if any.

Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-07-29 12:05:23 +02:00
Vivek Goyal
72e4848181 ovl: move some common code in a function
ovl_create_upper() and ovl_create_over_whiteout() seem to be sharing some
common code which can be moved into a separate function.  No functionality
change.

Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-07-29 12:05:23 +02:00
Andreas Gruenbacher
58ed4e70f2 ovl: store ovl_entry in inode->i_private for all inodes
Previously this was only done for directory inodes.  Doing so for all
inodes makes for a nice cleanup in ovl_permission at zero cost.

Inodes are not shared for hard links on the overlay, so this works fine.

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-07-29 12:05:22 +02:00
Miklos Szeredi
eead4f2dc4 ovl: use generic_delete_inode
No point in keeping overlay inodes around since they will never be reused.

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-07-29 12:05:22 +02:00
Miklos Szeredi
c1b2cc1a76 ovl: check mounter creds on underlying lookup
The hash salting changes meant that we can no longer reuse the hash in the
overlay dentry to look up the underlying dentry.

Instead of lookup_hash(), use lookup_one_len_unlocked() and swith to
mounter's creds (like we do for all other operations later in the series).

Now the lookup_hash() export introduced in 4.6 by 3c9fe8cdff1b ("vfs: add
lookup_hash() helper") is unused and can possibly be removed; its
usefulness negated by the hash salting and the idea that mounter's creds
should be used on operations on underlying filesystems.

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Fixes: 8387ff2577eb ("vfs: make the string hashes salt the hash")
2016-07-29 12:05:22 +02:00
Linus Torvalds
c624c86615 This is mostly clean ups and small fixes. Some of the more visible
changes are:
 
  . The function pid code uses the event pid filtering logic
  . [ku]probe events have access to current->comm
  . trace_printk now has sample code
  . PCI devices now trace physical addresses
  . stack tracing has less unnessary functions traced
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Merge tag 'trace-v4.8' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing updates from Steven Rostedt:
 "This is mostly clean ups and small fixes.  Some of the more visible
  changes are:

   - The function pid code uses the event pid filtering logic
   - [ku]probe events have access to current->comm
   - trace_printk now has sample code
   - PCI devices now trace physical addresses
   - stack tracing has less unnessary functions traced"

* tag 'trace-v4.8' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  printk, tracing: Avoiding unneeded blank lines
  tracing: Use __get_str() when manipulating strings
  tracing, RAS: Cleanup on __get_str() usage
  tracing: Use outer () on __get_str() definition
  ftrace: Reduce size of function graph entries
  tracing: Have HIST_TRIGGERS select TRACING
  tracing: Using for_each_set_bit() to simplify trace_pid_write()
  ftrace: Move toplevel init out of ftrace_init_tracefs()
  tracing/function_graph: Fix filters for function_graph threshold
  tracing: Skip more functions when doing stack tracing of events
  tracing: Expose CPU physical addresses (resource values) for PCI devices
  tracing: Show the preempt count of when the event was called
  tracing: Add trace_printk sample code
  tracing: Choose static tp_printk buffer by explicit nesting count
  tracing: expose current->comm to [ku]probe events
  ftrace: Have set_ftrace_pid use the bitmap like events do
  tracing: Move pid_list write processing into its own function
  tracing: Move the pid_list seq_file functions to be global
  tracing: Move filtered_pid helper functions into trace.c
  tracing: Make the pid filtering helper functions global
2016-07-28 18:20:09 -07:00
Linus Torvalds
f0c98ebc57 libnvdimm for 4.8
1/ Replace pcommit with ADR / directed-flushing:
    The pcommit instruction, which has not shipped on any product, is
    deprecated. Instead, the requirement is that platforms implement either
    ADR, or provide one or more flush addresses per nvdimm. ADR
    (Asynchronous DRAM Refresh) flushes data in posted write buffers to the
    memory controller on a power-fail event. Flush addresses are defined in
    ACPI 6.x as an NVDIMM Firmware Interface Table (NFIT) sub-structure:
    "Flush Hint Address Structure". A flush hint is an mmio address that
    when written and fenced assures that all previous posted writes
    targeting a given dimm have been flushed to media.
 
 2/ On-demand ARS (address range scrub):
    Linux uses the results of the ACPI ARS commands to track bad blocks
    in pmem devices.  When latent errors are detected we re-scrub the media
    to refresh the bad block list, userspace can also request a re-scrub at
    any time.
 
 3/ Support for the Microsoft DSM (device specific method) command format.
 
 4/ Support for EDK2/OVMF virtual disk device memory ranges.
 
 5/ Various fixes and cleanups across the subsystem.
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Merge tag 'libnvdimm-for-4.8' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm

Pull libnvdimm updates from Dan Williams:

 - Replace pcommit with ADR / directed-flushing.

   The pcommit instruction, which has not shipped on any product, is
   deprecated.  Instead, the requirement is that platforms implement
   either ADR, or provide one or more flush addresses per nvdimm.

   ADR (Asynchronous DRAM Refresh) flushes data in posted write buffers
   to the memory controller on a power-fail event.

   Flush addresses are defined in ACPI 6.x as an NVDIMM Firmware
   Interface Table (NFIT) sub-structure: "Flush Hint Address Structure".
   A flush hint is an mmio address that when written and fenced assures
   that all previous posted writes targeting a given dimm have been
   flushed to media.

 - On-demand ARS (address range scrub).

   Linux uses the results of the ACPI ARS commands to track bad blocks
   in pmem devices.  When latent errors are detected we re-scrub the
   media to refresh the bad block list, userspace can also request a
   re-scrub at any time.

 - Support for the Microsoft DSM (device specific method) command
   format.

 - Support for EDK2/OVMF virtual disk device memory ranges.

 - Various fixes and cleanups across the subsystem.

* tag 'libnvdimm-for-4.8' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm: (41 commits)
  libnvdimm-btt: Delete an unnecessary check before the function call "__nd_device_register"
  nfit: do an ARS scrub on hitting a latent media error
  nfit: move to nfit/ sub-directory
  nfit, libnvdimm: allow an ARS scrub to be triggered on demand
  libnvdimm: register nvdimm_bus devices with an nd_bus driver
  pmem: clarify a debug print in pmem_clear_poison
  x86/insn: remove pcommit
  Revert "KVM: x86: add pcommit support"
  nfit, tools/testing/nvdimm/: unify shutdown paths
  libnvdimm: move ->module to struct nvdimm_bus_descriptor
  nfit: cleanup acpi_nfit_init calling convention
  nfit: fix _FIT evaluation memory leak + use after free
  tools/testing/nvdimm: add manufacturing_{date|location} dimm properties
  tools/testing/nvdimm: add virtual ramdisk range
  acpi, nfit: treat virtual ramdisk SPA as pmem region
  pmem: kill __pmem address space
  pmem: kill wmb_pmem()
  libnvdimm, pmem: use nvdimm_flush() for namespace I/O writes
  fs/dax: remove wmb_pmem()
  libnvdimm, pmem: flush posted-write queues on shutdown
  ...
2016-07-28 17:38:16 -07:00
Linus Torvalds
1c88e19b0f Merge branch 'akpm' (patches from Andrew)
Merge more updates from Andrew Morton:
 "The rest of MM"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (101 commits)
  mm, compaction: simplify contended compaction handling
  mm, compaction: introduce direct compaction priority
  mm, thp: remove __GFP_NORETRY from khugepaged and madvised allocations
  mm, page_alloc: make THP-specific decisions more generic
  mm, page_alloc: restructure direct compaction handling in slowpath
  mm, page_alloc: don't retry initial attempt in slowpath
  mm, page_alloc: set alloc_flags only once in slowpath
  lib/stackdepot.c: use __GFP_NOWARN for stack allocations
  mm, kasan: switch SLUB to stackdepot, enable memory quarantine for SLUB
  mm, kasan: account for object redzone in SLUB's nearest_obj()
  mm: fix use-after-free if memory allocation failed in vma_adjust()
  zsmalloc: Delete an unnecessary check before the function call "iput"
  mm/memblock.c: fix index adjustment error in __next_mem_range_rev()
  mem-hotplug: alloc new page from a nearest neighbor node when mem-offline
  mm: optimize copy_page_to/from_iter_iovec
  mm: add cond_resched() to generic_swapfile_activate()
  Revert "mm, mempool: only set __GFP_NOMEMALLOC if there are free elements"
  mm, compaction: don't isolate PageWriteback pages in MIGRATE_SYNC_LIGHT mode
  mm: hwpoison: remove incorrect comments
  make __section_nr() more efficient
  ...
2016-07-28 16:36:48 -07:00
Andy Lutomirski
d30dd8be06 mm: track NR_KERNEL_STACK in KiB instead of number of stacks
Currently, NR_KERNEL_STACK tracks the number of kernel stacks in a zone.
This only makes sense if each kernel stack exists entirely in one zone,
and allowing vmapped stacks could break this assumption.

Since frv has THREAD_SIZE < PAGE_SIZE, we need to track kernel stack
allocations in a unit that divides both THREAD_SIZE and PAGE_SIZE on all
architectures.  Keep it simple and use KiB.

Link: http://lkml.kernel.org/r/083c71e642c5fa5f1b6898902e1b2db7b48940d4.1468523549.git.luto@kernel.org
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Vladimir Davydov <vdavydov@virtuozzo.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com>
Reviewed-by: Vladimir Davydov <vdavydov@virtuozzo.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-07-28 16:07:41 -07:00
Mel Gorman
11fb998986 mm: move most file-based accounting to the node
There are now a number of accounting oddities such as mapped file pages
being accounted for on the node while the total number of file pages are
accounted on the zone.  This can be coped with to some extent but it's
confusing so this patch moves the relevant file-based accounted.  Due to
throttling logic in the page allocator for reliable OOM detection, it is
still necessary to track dirty and writeback pages on a per-zone basis.

[mgorman@techsingularity.net: fix NR_ZONE_WRITE_PENDING accounting]
  Link: http://lkml.kernel.org/r/1468404004-5085-5-git-send-email-mgorman@techsingularity.net
Link: http://lkml.kernel.org/r/1467970510-21195-20-git-send-email-mgorman@techsingularity.net
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Hillf Danton <hillf.zj@alibaba-inc.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Rik van Riel <riel@surriel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-07-28 16:07:41 -07:00
Mel Gorman
4b9d0fab71 mm: rename NR_ANON_PAGES to NR_ANON_MAPPED
NR_FILE_PAGES  is the number of        file pages.
NR_FILE_MAPPED is the number of mapped file pages.
NR_ANON_PAGES  is the number of mapped anon pages.

This is unhelpful naming as it's easy to confuse NR_FILE_MAPPED and
NR_ANON_PAGES for mapped pages.  This patch renames NR_ANON_PAGES so we
have

NR_FILE_PAGES  is the number of        file pages.
NR_FILE_MAPPED is the number of mapped file pages.
NR_ANON_MAPPED is the number of mapped anon pages.

Link: http://lkml.kernel.org/r/1467970510-21195-19-git-send-email-mgorman@techsingularity.net
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Hillf Danton <hillf.zj@alibaba-inc.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Rik van Riel <riel@surriel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-07-28 16:07:41 -07:00
Mel Gorman
50658e2e04 mm: move page mapped accounting to the node
Reclaim makes decisions based on the number of pages that are mapped but
it's mixing node and zone information.  Account NR_FILE_MAPPED and
NR_ANON_PAGES pages on the node.

Link: http://lkml.kernel.org/r/1467970510-21195-18-git-send-email-mgorman@techsingularity.net
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Hillf Danton <hillf.zj@alibaba-inc.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Rik van Riel <riel@surriel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-07-28 16:07:41 -07:00
Michal Hocko
44a70adec9 mm, oom_adj: make sure processes sharing mm have same view of oom_score_adj
oom_score_adj is shared for the thread groups (via struct signal) but this
is not sufficient to cover processes sharing mm (CLONE_VM without
CLONE_SIGHAND) and so we can easily end up in a situation when some
processes update their oom_score_adj and confuse the oom killer.  In the
worst case some of those processes might hide from the oom killer
altogether via OOM_SCORE_ADJ_MIN while others are eligible.  OOM killer
would then pick up those eligible but won't be allowed to kill others
sharing the same mm so the mm wouldn't release the mm and so the memory.

It would be ideal to have the oom_score_adj per mm_struct because that is
the natural entity OOM killer considers.  But this will not work because
some programs are doing

	vfork()
	set_oom_adj()
	exec()

We can achieve the same though.  oom_score_adj write handler can set the
oom_score_adj for all processes sharing the same mm if the task is not in
the middle of vfork.  As a result all the processes will share the same
oom_score_adj.  The current implementation is rather pessimistic and
checks all the existing processes by default if there is more than 1
holder of the mm but we do not have any reliable way to check for external
users yet.

Link: http://lkml.kernel.org/r/1466426628-15074-5-git-send-email-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Cc: Vladimir Davydov <vdavydov@virtuozzo.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-07-28 16:07:41 -07:00
Michal Hocko
1d5f0acbc6 proc, oom_adj: extract oom_score_adj setting into a helper
Currently we have two proc interfaces to set oom_score_adj.  The legacy
/proc/<pid>/oom_adj and /proc/<pid>/oom_score_adj which both have their
specific handlers.  Big part of the logic is duplicated so extract the
common code into __set_oom_adj helper.  Legacy knob still expects some
details slightly different so make sure those are handled same way - e.g.
the legacy mode ignores oom_score_adj_min and it warns about the usage.

This patch shouldn't introduce any functional changes.

Link: http://lkml.kernel.org/r/1466426628-15074-4-git-send-email-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Cc: Vladimir Davydov <vdavydov@virtuozzo.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-07-28 16:07:41 -07:00
Michal Hocko
f913da596a proc, oom: drop bogus sighand lock
Oleg has pointed out that can simplify both oom_adj_{read,write} and
oom_score_adj_{read,write} even further and drop the sighand lock.  The
main purpose of the lock was to protect p->signal from going away but this
will not happen since ea6d290ca34c ("signals: make task_struct->signal
immutable/refcountable").

The other role of the lock was to synchronize different writers,
especially those with CAP_SYS_RESOURCE.  Introduce a mutex for this
purpose.  Later patches will need this lock anyway.

Suggested-by: Oleg Nesterov <oleg@redhat.com>
Link: http://lkml.kernel.org/r/1466426628-15074-3-git-send-email-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Cc: Vladimir Davydov <vdavydov@virtuozzo.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-07-28 16:07:41 -07:00
Michal Hocko
d49fbf766d proc, oom: drop bogus task_lock and mm check
Series "Handle oom bypass more gracefully", V5

The following 10 patches should put some order to very rare cases of mm
shared between processes and make the paths which bypass the oom killer
oom reapable and therefore much more reliable finally.  Even though mm
shared outside of thread group is rare (either vforked tasks for a short
period, use_mm by kernel threads or exotic thread model of
clone(CLONE_VM) without CLONE_SIGHAND) it is better to cover them.  Not
only it makes the current oom killer logic quite hard to follow and
reason about it can lead to weird corner cases.  E.g.  it is possible to
select an oom victim which shares the mm with unkillable process or
bypass the oom killer even when other processes sharing the mm are still
alive and other weird cases.

Patch 1 drops bogus task_lock and mm check from oom_{score_}adj_write.
This can be considered a bug fix with a low impact as nobody has noticed
for years.

Patch 2 drops sighand lock because it is not needed anymore as pointed
by Oleg.

Patch 3 is a clean up of oom_score_adj handling and a preparatory work
for later patches.

Patch 4 enforces oom_adj_score to be consistent between processes
sharing the mm to behave consistently with the regular thread groups.
This can be considered a user visible behavior change because one thread
group updating oom_score_adj will affect others which share the same mm
via clone(CLONE_VM).  I argue that this should be acceptable because we
already have the same behavior for threads in the same thread group and
sharing the mm without signal struct is just a different model of
threading.  This is probably the most controversial part of the series,
I would like to find some consensus here.  There were some suggestions
to hook some counter/oom_score_adj into the mm_struct but I feel that
this is not necessary right now and we can rely on proc handler +
oom_kill_process to DTRT.  I can be convinced otherwise but I strongly
think that whatever we do the userspace has to have a way to see the
current oom priority as consistently as possible.

Patch 5 makes sure that no vforked task is selected if it is sharing the
mm with oom unkillable task.

Patch 6 ensures that all user tasks sharing the mm are killed which in
turn makes sure that all oom victims are oom reapable.

Patch 7 guarantees that task_will_free_mem will always imply reapable
bypass of the oom killer.

Patch 8 is new in this version and it addresses an issue pointed out by
0-day OOM report where an oom victim was reaped several times.

Patch 9 puts an upper bound on how many times oom_reaper tries to reap a
task and hides it from the oom killer to move on when no progress can be
made.  This will give an upper bound to how long an oom_reapable task
can block the oom killer from selecting another victim if the oom_reaper
is not able to reap the victim.

Patch 10 tries to plug the (hopefully) last hole when we can still lock
up when the oom victim is shared with oom unkillable tasks (kthreads and
global init).  We just try to be best effort in that case and rather
fallback to kill something else than risk a lockup.

This patch (of 10):

Both oom_adj_write and oom_score_adj_write are using task_lock, check for
task->mm and fail if it is NULL.  This is not needed because the
oom_score_adj is per signal struct so we do not need mm at all.  The code
has been introduced by 3d5992d2ac7d ("oom: add per-mm oom disable count")
but we do not do per-mm oom disable since c9f01245b6a7 ("oom: remove
oom_disable_count").

The task->mm check is even not correct because the current thread might
have exited but the thread group might be still alive - e.g.  thread group
leader would lead that echo $VAL > /proc/pid/oom_score_adj would always
fail with EINVAL while /proc/pid/task/$other_tid/oom_score_adj would
succeed.  This is unexpected at best.

Remove the lock along with the check to fix the unexpected behavior and
also because there is not real need for the lock in the first place.

Link: http://lkml.kernel.org/r/1466426628-15074-2-git-send-email-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Vladimir Davydov <vdavydov@virtuozzo.com>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-07-28 16:07:41 -07:00
Scott Bauer
10eec60ce7 vfs: ioctl: prevent double-fetch in dedupe ioctl
This prevents a double-fetch from user space that can lead to to an
undersized allocation and heap overflow.

Fixes: 54dbc1517237 ("vfs: hoist the btrfs deduplication ioctl to the vfs")
Signed-off-by: Scott Bauer <sbauer@plzdonthack.me>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-07-28 15:23:12 -07:00
Linus Torvalds
69c4289449 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial
Pull trivial tree updates from Jiri Kosina.

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial:
  fat: fix error message for bogus number of directory entries
  fat: fix typo s/supeblock/superblock/
  ASoC: max9877: Remove unused function declaration
  dw2102: don't output spurious blank lines to the kernel log
  init: fix Kconfig text
  ARM: io: fix comment grammar
  ocfs: fix ocfs2_xattr_user_get() argument name
  scsi/qla2xxx: Remove erroneous unused macro qla82xx_get_temp_val1()
2016-07-28 14:22:25 -07:00
Linus Torvalds
76d5b28bba Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs
Pull quota update from Jan Kara:
 "time64 support for quota"

* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs:
  quota: use time64_t internally
2016-07-28 13:53:23 -07:00
Linus Torvalds
6784725ab0 Merge branch 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull vfs updates from Al Viro:
 "Assorted cleanups and fixes.

  Probably the most interesting part long-term is ->d_init() - that will
  have a bunch of followups in (at least) ceph and lustre, but we'll
  need to sort the barrier-related rules before it can get used for
  really non-trivial stuff.

  Another fun thing is the merge of ->d_iput() callers (dentry_iput()
  and dentry_unlink_inode()) and a bunch of ->d_compare() ones (all
  except the one in __d_lookup_lru())"

* 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (26 commits)
  fs/dcache.c: avoid soft-lockup in dput()
  vfs: new d_init method
  vfs: Update lookup_dcache() comment
  bdev: get rid of ->bd_inodes
  Remove last traces of ->sync_page
  new helper: d_same_name()
  dentry_cmp(): use lockless_dereference() instead of smp_read_barrier_depends()
  vfs: clean up documentation
  vfs: document ->d_real()
  vfs: merge .d_select_inode() into .d_real()
  unify dentry_iput() and dentry_unlink_inode()
  binfmt_misc: ->s_root is not going anywhere
  drop redundant ->owner initializations
  ufs: get rid of redundant checks
  orangefs: constify inode_operations
  missed comment updates from ->direct_IO() prototype change
  file_inode(f)->i_mapping is f->f_mapping
  trim fsnotify hooks a bit
  9p: new helper - v9fs_parent_fid()
  debugfs: ->d_parent is never NULL or negative
  ...
2016-07-28 12:59:05 -07:00
Linus Torvalds
554828ee0d Merge branch 'salted-string-hash'
This changes the vfs dentry hashing to mix in the parent pointer at the
_beginning_ of the hash, rather than at the end.

That actually improves both the hash and the code generation, because we
can move more of the computation to the "static" part of the dcache
setup, and do less at lookup runtime.

It turns out that a lot of other hash users also really wanted to mix in
a base pointer as a 'salt' for the hash, and so the slightly extended
interface ends up working well for other cases too.

Users that want a string hash that is purely about the string pass in a
'salt' pointer of NULL.

* merge branch 'salted-string-hash':
  fs/dcache.c: Save one 32-bit multiply in dcache lookup
  vfs: make the string hashes salt the hash
2016-07-28 12:26:31 -07:00
Benjamin Coddington
944171cbf4 pNFS: Actively set attributes as invalid if LAYOUTCOMMIT is outstanding
A LAYOUTCOMMIT then subsequent GETATTR may both return the same attributes,
and in that case NFS_INO_INVALID_ATTR is never set on the second pass
through nfs_update_inode().  The existing check to skip the clearing of
NFS_INO_INVALID_ATTR if a LAYOUTCOMMIT is outstanding does not help in this
case (see commit 10b7e9ad4488: "pNFS: Don't mark the inode as revalidated
if a LAYOUTCOMMIT is outstanding").  We know that if a LAYOUTCOMMIT is
outstanding then attributes will need upating, so always set
NFS_INO_INVALID_ATTR.

Signed-off-by: Benjamin Coddington <bcodding@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2016-07-28 14:49:08 -04:00
Pavel Shilovsky
7893242e24 CIFS: Fix a possible invalid memory access in smb2_query_symlink()
During following a symbolic link we received err_buf from SMB2_open().
While the validity of SMB2 error response is checked previously
in smb2_check_message() a symbolic link payload is not checked at all.
Fix it by adding such checks.

Cc: Dan Carpenter <dan.carpenter@oracle.com>
CC: Stable <stable@vger.kernel.org>
Signed-off-by: Pavel Shilovsky <pshilovsky@samba.org>
Signed-off-by: Steve French <smfrench@gmail.com>
2016-07-27 22:55:56 -05:00
Aurelien Aptel
a6b5058faf fs/cifs: make share unaccessible at root level mountable
if, when mounting //HOST/share/sub/dir/foo we can query /sub/dir/foo but
not any of the path components above:

- store the /sub/dir/foo prefix in the cifs super_block info
- in the superblock, set root dentry to the subpath dentry (instead of
  the share root)
- set a flag in the superblock to remember it
- use prefixpath when building path from a dentry

fixes bso#8950

Signed-off-by: Aurelien Aptel <aaptel@suse.com>
CC: Stable <stable@vger.kernel.org>
Reviewed-by: Pavel Shilovsky <pshilovsky@samba.org>
Signed-off-by: Steve French <smfrench@gmail.com>
2016-07-27 22:50:55 -05:00
Nicolas Pitre
002d2f01f1 m68k: enable binfmt_flat on systems with an MMU
Now that the generic changes are in place, this can be enabled on m68k
with the use of proper user space accessors in the flat_get_addr_from_rp()
and flat_put_addr_at_rp() handlers as rp actually holds a user space
address.

Signed-off-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Greg Ungerer <gerg@linux-m68k.org>
2016-07-28 13:29:13 +10:00
Nicolas Pitre
472f95f32d binfmt_flat: allow compressed flat binary format to work on MMU systems
Let's take the simple and obvious approach by decompressing the binary
into a kernel buffer and then copying it to user space.  Those who are
looking for top performance on an MMU system are unlikely to choose this
executable format anyway.

Signed-off-by: Nicolas Pitre <nico@linaro.org>
Reviewed-by: Greg Ungerer <gerg@linux-m68k.org>
Signed-off-by: Greg Ungerer <gerg@linux-m68k.org>
2016-07-28 13:29:12 +10:00
Nicolas Pitre
015feacf93 binfmt_flat: add MMU-specific support
Not much else to do at this point except for the different stack setups.

Signed-off-by: Nicolas Pitre <nico@linaro.org>
Reviewed-by: Greg Ungerer <gerg@linux-m68k.org>
Signed-off-by: Greg Ungerer <gerg@linux-m68k.org>
2016-07-28 13:29:12 +10:00
Nicolas Pitre
af521f92dc binfmt_flat: update libraries' data segment pointer with userspace accessors
This is needed on systems with a MMU.  This also gets rid of the
strangest C code I've seen lateli i.e. an integer indexed with a
pointer value within square brackets. That really looked backwards.

Signed-off-by: Nicolas Pitre <nico@linaro.org>
Reviewed-by: Greg Ungerer <gerg@linux-m68k.org>
Signed-off-by: Greg Ungerer <gerg@linux-m68k.org>
2016-07-28 13:29:11 +10:00
Nicolas Pitre
467aa1465a binfmt_flat: use clear_user() rather than memset() to clear .bss
This is needed on systems with a MMU.

Signed-off-by: Nicolas Pitre <nico@linaro.org>
Reviewed-by: Greg Ungerer <gerg@linux-m68k.org>
Signed-off-by: Greg Ungerer <gerg@linux-m68k.org>
2016-07-28 13:29:11 +10:00
Nicolas Pitre
1b2ce442ea binfmt_flat: use proper user space accessors with old relocs code
Signed-off-by: Nicolas Pitre <nico@linaro.org>
Reviewed-by: Greg Ungerer <gerg@linux-m68k.org>
Signed-off-by: Greg Ungerer <gerg@linux-m68k.org>
2016-07-28 13:28:58 +10:00
Phil Turnbull
955818cd5b ceph: Correctly return NXIO errors from ceph_llseek
ceph_llseek does not correctly return NXIO errors because the 'out' path
always returns 'offset'.

Fixes: 06222e491e66 ("fs: handle SEEK_HOLE/SEEK_DATA properly in all fs's that define their own llseek")
Signed-off-by: Phil Turnbull <phil.turnbull@oracle.com>
Signed-off-by: Yan, Zheng <zyan@redhat.com>
2016-07-28 03:00:45 +02:00
Nikolay Borisov
6b1a9a6c54 ceph: Mark the file cache as unreclaimable
Ceph creates multiple caches with the SLAB_RECLAIMABLE flag set, so
that it can satisfy its internal needs. Inspecting the code shows that
most of the caches are indeed reclaimable since they are directly
related to the generic inode/dentry shrinkers. However, one of the
cache used to satisfy struct file is not reclaimable since its
entries are freed only when the last reference to the file is
dropped. If a heavily loaded node opens a lot of files it can
introduce non-trivial discrepancies between memory shown as reclaimable
and what is actually reclaimed when drop_caches is used.

Fix this by removing the reclaimable flag for the file's cache.

Signed-off-by: Nikolay Borisov <n.borisov.lkml@gmail.com>
Signed-off-by: Yan, Zheng <zyan@redhat.com>
2016-07-28 03:00:45 +02:00
Yan, Zheng
c8799fc467 ceph: optimize cap flush waiting
Add a 'wake' flag to ceph_cap_flush struct, which indicates if there
is someone waiting for it to finish. When getting flush ack message,
we check the 'wake' flag in corresponding ceph_cap_flush struct to
decide if we should wake up waiters. One corner case is that the
acked cap flush has 'wake' flags is set, but it is not the first one
on the flushing list. We do not wake up waiters in this case, set
'wake' flags of preceding ceph_cap_flush struct instead

Signed-off-by: Yan, Zheng <zyan@redhat.com>
2016-07-28 03:00:45 +02:00
Yan, Zheng
ed9b430c9b ceph: cleanup ceph_flush_snaps()
This patch devide __ceph_flush_snaps() into two stags. In the first
stage, __ceph_flush_snaps() assign snapcaps flush TIDs and add them
to cap flush lists. __ceph_flush_snaps() keeps holding the
i_ceph_lock in this stagge. So inode's auth cap can not change. In
the second stage, __ceph_flush_snaps() send flushsnap cap messages.
i_ceph_lock is unlocked before sending each cap message. If auth cap
changes in the middle, __ceph_flush_snaps() just stops. This is OK
because kick_flushing_inode_caps() will re-send flushsnap cap messages
to inode's new auth MDS.

Signed-off-by: Yan, Zheng <zyan@redhat.com>
2016-07-28 03:00:44 +02:00
Yan, Zheng
7bc00fddb9 ceph: kick cap flushes before sending other cap message
If ceph_check_caps() wants to send cap message to a recovering MDS,
make sure it kicks cap flushes first.

Signed-off-by: Yan, Zheng <zyan@redhat.com>
2016-07-28 03:00:44 +02:00
Yan, Zheng
70220ac8c2 ceph: introduce an inode flag to indicates if snapflush is needed
Signed-off-by: Yan, Zheng <zyan@redhat.com>
2016-07-28 03:00:43 +02:00
Yan, Zheng
13c2b57d81 ceph: avoid sending duplicated cap flush message
make ceph_kick_flushing_caps() ignore inodes whose cap flushes
have already been re-sent by ceph_early_kick_flushing_caps()

Signed-off-by: Yan, Zheng <zyan@redhat.com>
2016-07-28 03:00:43 +02:00
Yan, Zheng
0e29438789 ceph: unify cap flush and snapcap flush
This patch includes following changes
- Assign flush tid to snapcap flush
- Remove session's s_cap_snaps_flushing list. Add inode to session's
  s_cap_flushing list instead. Inode is removed from the list when
  there is no pending snapcap flush or cap flush.
- make __kick_flushing_caps() re-send both snapcap flushes and cap
  flushes.

Signed-off-by: Yan, Zheng <zyan@redhat.com>
2016-07-28 03:00:42 +02:00
Yan, Zheng
e4500b5e35 ceph: use list instead of rbtree to track cap flushes
We don't have requirement of searching cap flush by TID. In most cases,
we just need to know TID of the oldest cap flush. List is ideal for this
usage.

Signed-off-by: Yan, Zheng <zyan@redhat.com>
2016-07-28 03:00:42 +02:00
Yan, Zheng
3609404f8c ceph: update types of some local varibles
Signed-off-by: Yan, Zheng <zyan@redhat.com>
2016-07-28 03:00:42 +02:00
Yan, Zheng
3469ed0d14 ceph: include 'follows' of pending snapflush in cap reconnect message
This helps the recovering MDS to reconstruct the internal states that
tracking pending snapflush.

Signed-off-by: Yan, Zheng <zyan@redhat.com>
2016-07-28 03:00:41 +02:00
Yan, Zheng
121f22a19a ceph: update cap reconnect message to version 3
Signed-off-by: Yan, Zheng <zyan@redhat.com>
2016-07-28 03:00:41 +02:00
Yan, Zheng
430afbadd6 ceph: mount non-default filesystem by name
To mount non-default filesytem, user currently needs to provide mds
namespace ID. This is inconvenience.

This patch makes user be able to mount filesystem by name. If user
wants to mount non-default filesystem. Client first subscribes to
fsmap.user. Subscribe to mdsmap.<ID> after getting ID of filesystem.

Signed-off-by: Yan, Zheng <zyan@redhat.com>
2016-07-28 03:00:40 +02:00
Jeff Layton
f49d1e058d ceph: handle LOOKUP_RCU in ceph_d_revalidate
We can now handle the snapshot cases under RCU, as well as the
non-snapshot case when we don't need to queue up a lease renewal
allow LOOKUP_RCU walks to proceed under those conditions.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Reviewed-by: Yan, Zheng <zyan@redhat.com>
2016-07-28 03:00:39 +02:00
Jeff Layton
14fb9c9efe ceph: allow dentry_lease_is_valid to work under RCU walk
Under rcuwalk, we need to take extra care when dereferencing d_parent.
We want to do that once and pass a pointer to dentry_lease_is_valid.

Also, we must ensure that that function can handle the case where we're
racing with d_release. Check whether "di" is NULL under the d_lock, and
just return 0 if so.

Finally, we still need to kick off a renewal job if the lease is getting
close to expiration. If that's the case, then just drop out of rcuwalk
mode since that could block.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Reviewed-by: Yan, Zheng <zyan@redhat.com>
2016-07-28 03:00:39 +02:00
Jeff Layton
5b484a5131 ceph: clear d_fsinfo pointer under d_lock
To check for a valid dentry lease, we need to get at the
ceph_dentry_info. Under rcuwalk though, we may end up with a dentry that
is on its way to destruction. Since we need to take the d_lock in
dentry_lease_is_valid already, we can just ensure that we clear the
d_fsinfo pointer out under the same lock before destroying it.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Reviewed-by: Yan, Zheng <zyan@redhat.com>
2016-07-28 03:00:39 +02:00
Jeff Layton
8aa152c778 ceph: remove ceph_mdsc_lease_release
Nothing calls it.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Reviewed-by: Yan, Zheng <zyan@redhat.com>
2016-07-28 03:00:38 +02:00
Miklos Szeredi
9b16f03c47 ceph: don't use ->d_time
Pretty simple: just use ceph_dentry_info.time instead (which was already
there, unused).

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-07-28 03:00:35 +02:00
Colin Ian King
679f0b825d ceph: fix spelling mistake: "resgister" -> "register"
trivial fix to spelling mistake in pr_err message

Signed-off-by: Colin Ian King <colin.king@canonical.com>
2016-07-28 02:55:40 +02:00
Yan, Zheng
fce8515741 ceph: fix NULL dereference in ceph_queue_cap_snap()
old_snapc->seq is used in dout(...)

Signed-off-by: Yan, Zheng <zyan@redhat.com>
2016-07-28 02:55:40 +02:00